Attendees at Saturday night’s American Cinemateque screening of Monty Python’s iconic “Life of Brian” at the Aero received a bonus — six minutes of footage from the Pythonesque sci-fi farce “Absolutely Anything,” screened by director Terry Jones.

Simon Pegg and Kate Beckinsale star and the late Robin Williams voices Dennis the Dog. The Pythons are voicing key roles as a group of aliens who endow a disillusioned teacher (Pegg) with the power to do “absolutely anything” to see what a mess he’ll make of things — which is precisely what happens.

In a discussion with Cinemateque’s Grant Moninger, Jones explained that he and Gavin Scott had worked on the script for over two decades but shelved the project in 2003 when “Bruce Almighty” was released. “Five years later, Mike Medavoy asked me what project was at the bottom of my drawer,” he added.

He asked Williams to come on board during the Emmys in 2009.

Five years later, Williams came up with the key to the character after a recording session in San Francisco. “He rang me up as we were at San Francisco airport and said, ‘I’ve got a great idea — Dennis is a 16-year-old boy.'”

The clip showed Beckinsale’s character showing up unexpectedly as Pegg’s home, with Pegg explaining that Dennis’ voice from the bathroom is that of a plumber, who then yells, “Why don’t you shag her?”

Jones said Pythons John Cleese, Terry Gilliam, Michael Palin and Eric Idle are the voices of the aliens: “John does the chief alien;  Terry does the nasty alien who’s very small; Michael is the nice one and Eric is the wisecracker.”

Gavin Scott, who co-wrote the script with Jones, told Variety that Williams never wavered in his commitment to doing the film. “He was rock solid for us and so talented, so that makes his passing all the sadder,” he added.

As for “Life of Brian,” Jones explained the why of George Harrison’s brief appearance in the 1979 film — he had financed the film by mortgaging his house — and noted that Michael Palin voiced over Harrison’s “Hello” because it wasn’t loud enough. Jones directed “Brian” and starred as Brian’s mother Mandy.

“Absolutely Anything” producers are Terry Jones’ son Bill Jones and Ben Timlett. Medavoy and Chris Chesser are the exec producers.

The film was sold by GFM Films at Cannes and racked up sales to Lionsgate for the U.K. along with Germany (Telepool and Senator), Scandinavia (Svenske) and for Australasia to Icon. Bill Jones told Variety that “Absolutely Anything” may screen for buyers at Berlin.

As for Terry Jones, he’s working on documentaries on Charlie Chaplin and the 2008 economic crisis — with comedy mixed  in via dance numbers and charts. “It’s got Dad’s humor,” Bill Jones asserted.